In the catheter-based ultrasound imaging arena, increasing emphasis is being placed on intraluminal/intracavitary underfluid imaging for the purpose of directing precision therapy and diagnostics. A number of imaging catheter inventions have been proposed over the last few years. The basic concepts of a self-contained ultrasound catheter device have been described in the patents issued to Dr. James B. Seward and A. Jamil Tajik, such as U.S. Pat. Nos. 5,325,860 and 5,345,940, and are incorporated hereby by references. However, at present, underfluid ultrasound technology is principally limited to linear, sector, or cylindrical ultrasound array transducers which are optimized to obtain single tomographic planes of view. Additional planes are usually obtained by manipulation of the catheter or the stacking of images into a data set. Three-dimensional volumetric images have been small and of little clinical utility.
Presently rotatable multiplane arrays are primarily used in large transesophageal echocardiographic probes (see "Multiplane Transesophageal Echocardiography: Image Orientation, Examination Technique, Anatomic Correlations and Clinical Applications" by Seward J. B., et al. Mayo Clinic Proceedings, 68:523-551, 1993) and, to a lesser extent, for surface echocardiographic examinations (see "Multidimensional Ultrasonic Imaging for Cardiology" by McCann H. A. et al. Proc IEEE, 76:1063-1071, 1988; and U.S. Pat. No. 4,543,960 issued to Harui et al.) The patent discloses a catheter-based multiplane (conical data set) echocardiography scanhead. The ultrasound imaging scanhead is rotated to obtain multiple cross-sectional planes from within the cardiovascular system including the heart. This patent also discloses that it is possible to use the scanhead in a manner whereby cross-sectional views of the heart can be obtained along a variety of orientations. These catheter orientations are selectable by the operator while actually viewing the internal cardiovascular and surrounding structures on the monitor to which the scanhead is connected. The catheter-based multiplane echocardiographic technology permits the attainment of sequential tomographic images (i.e., a data set) from the confines of the cardiovascular system. Such multiplane transducers have been used to obtain a spatially sequenced set of images suitable for 3-dimensional image reconstruction (see "Three- and Four-Dimensional Cardiovascular Ultrasound Imaging: A New Era for Echocardiography" by Belohlavek M. et al. Mayo Clinic Proceedings 1993, 68:221-240).
There is a need in the art for a catheter-based intraluminal/intracavital transluminal imaging device capable of generating multiple fields of view while requiring no manipulation of the catheter. There is also a need for a catheter-based imaging device capable of providing spatially sequenced tomographic images that can be formed, i.e. coalesced, into a three-dimensional image by using a catheter-based multiplane array technology. There is further a need for a catheter-based imaging device capable of delivering diagnostic and therapeutic tools into a field of ultrasound generated by a multiplane phased array imaging ultrasound transducer.